This protocol is intended to assist pathologists in providing clinically useful and relevant information as a result of the examination of surgical specimens. Use of this protocol is intended to be entirely voluntary. If equally valid protocols or similar documents are applicable, the pathologist is, of course, free to follow those authorities. Indeed, the ultimate judgment regarding the propriety of any specific procedure must be made by the physician in light of the individual circumstances presented by a specific patient or specimen.
It should be understood that adherence to this protocol will not guarantee a successful result. Nevertheless, pathologists are urged to familiarize themselves with the document. Should a physician choose to deviate from the protocol based on the circumstances of a particular patient or specimen, the physician is advised to make a contemporaneous written notation of the reason for the procedure followed.
The College recognizes that this document may be used by hospitals, attorneys, managed care organizations, insurance carriers, and other payers. However, the document was developed solely as a tool to assist pathologists in the diagnostic process by providing information that reflects the state of relevant medical knowledge at the time the protocol was first published. It was not developed for credentialing, litigation, or reimbursement purposes. The College cautions that any uses of the protocol for these purposes involve considerations that are beyond the scope of this document.
PROTOCOL FOR THE EXAMINATION OF SPECIMENS FROM PATIENTS WITH CARCINOMAS OF THE SKIN, EXCLUDING EYELID, VULVA, AND PENIS
I. Biopsy
A. Clinical information
1. Patient identification
a. Name
b. Identification number
c. Age (birth date)
d. Gender
e. Skin type (eg, Fitzpatrick type, other)
2. Responsible physician(s)
3. Date of procedure
4. Other clinical information
a. Relevant history
(1) Duration of lesion
(2) Previous excision of present lesion
(3) Previous similar lesions
(4) Family history of similar lesions
(5) Immunosuppression
(6) Radiation exposure
b. Relevant findings
(1) Number of lesions and their distribution
(2) Nature of advancing borders of lesion
(3) Nature of pigmentation, if any
(4) Ulceration
(5) Palpable qualities of lesion (eg, hard, tender, nontender)
(6) Fixation to deeper tissues on palpation
5. Clinical diagnosis
6. Procedure (eg, punch biopsy, incisional biopsy)
a. Anatomic site of specimen(s)
B. Macroscopic examination
1. Specimen
a. Tissues received (specify nature and site)
b. Unfixed/fixed (specify fixative)
c. Number of pieces of tissue
d. Shape/type of specimen (eg, ellipse, punch core, shave fragments)
e. Dimensions
f. Results of intraoperative consultation, if performed
2. Tumor, if discernible
a. Location
b. Descriptive features
(1) Color (eg, pigmentation)
(2) Consistency
(3) Ulceration
(4) Hemorrhage
c. Dimensions
d. Configuration
3. Tissue submitted for microscopic examination
a. Submit all
b. Frozen section tissue fragment(s)
4. Special studies (specify) (eg, histochemical stains, immunohistochemistry, electron microscopy, flow cytometry, cytogenetics)
C. Microscopic evaluation
1. Tumor
a. Histologic type (note A)
b. Histologic grade, if applicable (note B)
c. Depth of invasion, if appropriate (note C)
(1) Measurement in millimeters for squamous carcinoma (note C)
d. Perineural invasion (note D)
e. Blood/lymphatic vessel invasion (note D)
f. Nature of advancing margin of tumor, if able to be evaluated (eg, pushing, infiltrative)* (note D)
* Applies principally to basal cell carcinomas.
2. Associated skin lesions
a. Actinic keratosis
b. Bowen disease
3. Additional pathologic findings, if present
4. Results of special studies (specify)
5. Comments
a. Correlation with intraoperative consultations, if any
b. Correlation with prior specimens, if any
c. Correlation with clinical findings, as appropriate
II. Excision
A. Clinical information
1. Patient identification
a. Name
b. Identification number
c. Age (birth date)
d. Gender
e. Skin type (eg, Fitzpatrick type, other)
2. Responsible physician(s)
3. Date of procedure
4. Other clinical information
a. Relevant history
(1) Duration of lesion
(2) Previous excision of present lesion
(3) Previous similar lesions
(4) Family history of similar lesions
(5) Immunosuppression
(6) Radiation exposure
b. Relevant findings
(1) Lesion number and distribution
(2) Nature of advancing borders of lesion
(3) Nature of pigmentation, if any
(4) Ulceration
(5) Palpable qualities of lesion (eg, hard, tender, nontender)
(6) Fixation to deeper tissues on palpation
c. Clinical diagnosis
d. Procedure
e. Anatomic site of specimen(s)
B. Macroscopic examination
1. Specimen
a. Tissues received (specify type and site)
b. Unfixed/fixed (specify fixative)
c. Orientation of specimen, if indicated by surgeon
d. Number of pieces of tissue
e. Shape/type of specimen (eg, ellipse, punch core, shave fragments, curettings)
f. Dimensions
g. Results of intraoperative consultation, if any
2. Tumor
a. Location
b. Configuration
c. Pigmentation (nature and extent)
d. Dimensions (3)
e. Descriptive characteristics
(1) Color
(2) Consistency
(3) Ulceration
(4) Fixation to other tissues
(5) Necrosis
(6) Hemorrhage
f. Estimated depth of invasion from skin surface (specify compartment, eg, deep dermis, subcutis)
3. Margins (specify if involved or uninvolved by tumor, if appropriate to specimen)
4. Regional lymph nodes, if any
a. Location (as specific as possible)
b. Number
c. Gross appearance (with measurement of macroscopically obvious tumor deposits within the nodes)
5. Additional pathologic findings, if present
a. Actinic keratoses
b. Melanocytic nevi
c. Other
6. Tissue submitted for microscopic examination (specify location in specimen of each)
7. Special studies (specify) (eg, histochemical stains, immunohistochemistry, electron microscopy, flow cytometry, cytogenetics)
C. Microscopic evaluation
1. Tumor
a. Histologic type (note A)
b. Histologic grade, if applicable (note B)
c. Depth of invasion (note C)
(1) Measurement in millimeters for squamous carcinoma (note C)
d. Perineural invasion (with extent) (note D)
e. Blood/lymphatic vessel invasion (with extent) (note D)
f. Nature of advancing margin of tumor (eg, pushing, infiltrative) (note D)
g. Presence and approximate percentage of extent of regression, if present* (note D)
h. Mitotic count per 10 high-power fields† (note D)
* Applies principally to basal cell carcinomas.
† Applies only to Merkel cell carcinomas.
2. Margins (note E)
3. Additional pathologic findings, if present
a. Actinic keratosis
b. Bowen disease
4. Regional lymph nodes (pN) (note F)
a. Number
b. Number containing metastases
(1) Measurement of metastatic focus
(2) Extranodal extension, if present
5. Metastases to other organs (pM)
6. Results of special studies (specify)
7. Comments
a. Correlation with intraoperative consultations, if any
b. Correlation with prior specimens, if any
c. Correlation with clinical findings, as appropriate
d. Comments on prognostic findings
EXPLANATORY NOTES
A: Histologic Subtypes.—The World Health Organization (WHO) classification of carcinomas of the skin is shown below.
Epidermal carcinomas
Basal cell carcinoma (BCC) and variants listed below:
Superficial BCC
Nodular BCC (solid, adenoid cystic)
Infiltrating BCC
Sclerosing BCC (desmoplastic, morpheic)
Fibroepithelial BCC1
BCC with adnexal differentiation
Follicular BCC
Eccrine BCC
Basosquamous carcinoma
Keratotic BCC
Pigmented BCC
BCC in basal cell nevus syndrome
Micronodular BCC
Squamous cell carcinoma (SCC) and variants listed below:
Spindle cell (sarcomatoid) SCC
Acantholytic SCC
Verrucous SCC
SCC with horn formation
Lymphoepithelial SCC
Variants not included in the WHO classification are as follows:
Papillary SCC
Clear cell SCC
Small cell SCC
Posttraumatic (eg, Marjolin ulcer)
Metaplastic (carcinosarcomatous) SCC
Paget disease
Mammary Paget disease
Extramammary Paget disease
Adnexal carcinomas
Eccrine carcinoma and variants listed below:
Sclerosing sweat duct carcinoma (syringomatous carcinoma, microcystic adnexal carcinoma)
Malignant mixed tumor of the skin (malignant chondroid syringoma)
Porocarcinoma
Malignant nodular hidradenoma
Malignant eccrine spiradenoma
Mucinous eccrine carcinoma
Adenoid cystic eccrine carcinoma
Aggressive digital papillary adenoma/adenocarcinoma
Apocrine carcinoma
Sebaceous carcinoma
Tricholemmocarcinoma and its variant listed below:
Malignant pilomatricoma (matrical carcinoma)
Note.—Merkel cell carcinoma is not included in the WHO classification of skin tumors.
B: Histologic Grade.—Histologic grading is appropriate only for SCCs and adnexal carcinomas. Suggested histologic grades are as follows:
Grade 1 Well differentiated
Grade 2 Moderately differentiated
Grade 3 Poorly differentiated
Grade 4 Undifferentiated
C: TNM and Stage Groupings.—The authors of this protocol recommend the TNM Staging System of the American Joint Committee on Cancer/International Union Against Cancer (AJCC/UICC).1,2
* Optional expansions suggested by the TNM Supplement.3
Important Note.—By AJCC/UICC convention, the designation “T” refers to a primary tumor that has not been previously treated. The symbol “p” refers to the pathologic classification of the TNM, as opposed to the clinical classification and is based on gross and microscopic examination. pT entails a resection of the primary tumor or biopsy adequate to evaluate the highest pT category, pN entails removal of nodes adequate to validate lymph node metastasis, and pM implies microscopic examination of distant lesions. Clinical classification (cTNM) is usually carried out by the referring physician before treatment during initial evaluation of the patient or when pathologic classification is not possible.
Tumor remaining in a patient after cancer-directed therapy (eg, surgical resection for cure) is categorized by a system known as the R classification, shown below.
RX Presence of residual tumor cannot be assessed
R0 No residual tumor
R1 Microscopic residual tumor
R2 Macroscopic residual tumor
For the surgeon, the R classification may be useful to indicate the known or assumed status of the completeness of a surgical excision. For the pathologist, the R classification is relevant to the status of the margins of a surgical resection specimen; that is, tumor involving the resection margin on pathologic examination may be assumed to correspond to residual tumor in the patient and may be classified as macroscopic or microscopic according to the findings at the specimen margin(s).
In contrast, tumor remaining in a resection specimen from a patient who has undergone previous (neoadjuvant) treatment of any type (radiation therapy alone, chemotherapy therapy alone, or any combined modality treatment) is codified by the TNM using a prescript “y” (eg, ypT1). Thus, yTNM indicates the posttreatment status of the tumor. For many neoadjuvant therapies, the classification of residual disease may be a strong predictor of postoperative outcome. In addition, the ypTNM classification provides a standardized framework for the collection of data needed to accurately evaluate new neoadjuvant therapies.
In contrast to residual tumor, classification of a tumor as recurrent requires a documented disease-free interval after definitive therapy. Recurrent tumor may also be classified according to the TNM categories, but the prefix “r” (eg, rpT1) is used to indicate the recurrent status of the tumor.
D: Adverse Prognostic Factors.—Important adverse prognostic factors for cutaneous malignancies are as follows:
Basal cell carcinoma
Infiltrative, morpheaform, or micronodular histologic subtype
Invasion into deep subcutaneous fat, muscle, or cartilage
Perineural invasion
Positivity of surgical margins
Presence of scar within the tumor
Squamous cell carcinoma
Adenoid, basaloid, small cell, or spindle cell histologic subtypes
Posttraumatic clinicopathologic subtype
Extensive perineural, lymphatic, or vascular invasion
Invasion into subcutis
Positivity of surgical margins
Acantholytic subtype
Merkel cell carcinoma
Gross size >2 cm
Mitotic activity (10 division figures/10 high-power [×400] microscopic fields)
Extensive lymphatic or vascular invasion
Presence of associated Bowen disease
Divergent squamous differentiation in invasive tumor
Positivity of surgical margins
E: Margins.—If the specimen is oriented, the position of lateral margins involved by tumor should be indicated. A comment on margins is necessary only for excisional biopsies or formal resections. Measurements of distance from tumor to margins are generally not considered useful or helpful and need not be routinely reported. However, distance to margins may be reported in special circumstances and/or when requested by the treating physician.
F: Lymph Node Dissections.—Lymph node dissections are not routinely performed for any cutaneous malignancy. Therefore, a comment may be needed that documents the clinical nodal status (cN substage) instead of pathologic (pN substage) status in assembling the final stage grouping for the tumor.
Acknowledgments
Lyn Duncan, MD; Harley A. Haynes, MD; Gregg M. Menaker, MD; and Nicholas E. O'Connor, MD contributed to the development of this monograph.
References
Bibliography
* The protocol excludes malignant melanoma, sarcoma, and hematopoietic malignancy.
This protocol was developed by the Cancer Committee of the College of American Pathologists and submitted for editorial review and publication. It represents the views of the Cancer Committee and is not the official policy of the College of American Pathologists.
Reprints: See Archives of Pathology & Laboratory Medicine Web site at www.cap.org.